From Compendium of Worldly Lore
Master of the black art of demon summoning, the demonbinder keeps alive the sinister traditions of the old kingdoms. More than a thousand years ago the sorrcerous lands grew mighty on the strength of its unholy mages and cruel priest-lords. Although trafficking with demons contributes to its eventual downfall more than likely, secrets of the old lore still draw unscrupulous spellcasters who plunder the buried vaults of the long-vanished land in search of knowledge and power, as well as more principled researchers who pursue this forbidden lore to battle demons.
Demonbinders are most often clerics, sorcerers, or wizards. Bards and druids do not have access to the spells necessary to call up and command fiendish creatures, and the prestige class demands high spellcasting ability simply to qualify.
Role: Spell
Characteristics: Practitioners of summoning fiends with powerful controlling signs and spell substitution.
Source: Unapproachable East
Game Rule Information
The Demonbinder has the following game statistics.
Abilities: Charisma to influence demons and cast spells better. Dexterity and Constitution for staying alive and binding those demons.
Alignment: Any
Hit Die: d6
Starting Gold: N/A
Class Skills
The Demonbinder's class skills are Concentration (Con), Craft (Int), Decipher Script (Int), Diplomacy (Cha), Intimidate (Cha), Knowledge (arcana, the planes) (Int), Listen (Wis), Profession (Wis), Search (Int), Sense Motive (Wis), Spellcraft (Int), Spot (Wis)
Skill Points at 1st Level: (2 + Int modifier) × 4
Skill Points at Each Additional Level: 2 + Int modifier
Class Features
All of the following are class features of the Demonbinder.
Weapon and Armor Proficiency: A Demonbinder is proficient with whatever they were already proficient with prior to taking levels in this class.
Spells per Day: Beginning at 1st level, a demonbinder gains the ability to cast a small number of arcane spells. He gains arcane spells per day according to table 1-2. He must learn and choose his spells from the demonbinder spell list, below. The character's caster level is equal to his demonbinder level plus his levels in one other spellcasting class of his choice. To cast a spell, the demonbinder must have a Charisma score of at least 10 + the spell's level. Demonbinder bonus spells are based on Charisma, and saving throws against these spells have a DC of 10 + Caster level. Demonbinders prepare and cast their demonbinder spells as sorcerers, as shown below.
Fiendish Familiar: A demonbinder can call a fiendish familiar. Doing so takes a day and uses up magical materials that cost 100 gp. The demonbinder may choose either an imp or a quasit as a familiar, just as if he knew the Improved Familiar feat and were an arcane spellcaster of the appropriate level. The fiendish familiar is magically linked to its master just like a normal familiar. The imp or quasit uses the basic statistics for a creature of its kind as given in the Monster Manual, with the following exceptions. (Unless otherwise stated, for all fiendish familiar abilities dependent on the master's level, count only sorcerer/wizard levels and demonbinder levels, which stack for the purposes of determining the familiar's abilities.)
Hit Points: One-half of the master's total or the fiendish familiar's normal total, whichever is higher.
Attacks: Use the master's base attack bonus or the fiendish familiar's, whichever is better. Use the familiar's Dexterity or Strength modifier, whichever is greater, to get the familiar's melee attack bonus with unarmed attacks. Damage equals that of a normal creature of that kind.
Special Attacks: The fiendish familiar has all the special attacks of its kind.
Special Qualities: The fiendish familiar has all the special qualities of its kind.
Saving Throws: The fiendish familiar uses the master's base save bonuses if they are better than its own. The familiar uses its own ability score modifiers on saves, and it doesn't enjoy other bonuses that the demonbinder might have (such as from magic items or feats).
Skills: Use the normal skill ranks for a creature of that kind, modified by the fiendish familiar's own ability score modifiers.
Familiar Special Abilities: Use Table 3—19: Familiar Special Abilities in the Player's Handbook to determine additional abilities as you would for a normal familiar. The character may add any levels of sorcerer and/or wizard/ appropriate caster to his demonbinder class level for purposes of determining his fiendish familiar's special abilities.
Inimical Casting Ex: A Nar demonbinder knows how to employ spells that deflect the attacks of outsiders, regardless of alignment. When a demonbinder casts one of the spells listed below, he may choose one of the listed effects instead.
Magic Circle Against Good can be cast as Magic Circle Against Evil, Magic Circle Against Chaos, or Magic Circle Against Law.
Dispel Good may be cast as Dispel Chaos, Dispel Evil, or Dispel Law.
Blasphemy may be cast as Dictum, Holy Word, or Word of Chaos.
Unholy Aura may be cast as Holy Aura, Cloak of Chaos, or Shield of Law.
Iron Sign: On reaching 2nd level, a demonbinder learns how to fashion a special token known as an iron sign. Creating the token requires three days and 1,000 gp in magical materials. The iron sign is the size of a large amulet. The demonbinder can use it in one of two ways.
Calling Diagram: The iron sign functions as a calling diagram (see Conjuration under Schools of Magic in Chapter 10: Magic of the Player's Handbook) that combines a magic circle with dimensional anchor. The demonbinder need only set the token on a suitable surface, and no Spellcraft check is necessary to scribe the diagram. A creature held by the iron sign must remain within 5 feet of it and otherwise behaves as if it were completely enclosed in a suitably sized calling diagram.
The iron sign can hold a called creature for up to one day per caster level of the character who crafted it. Unlike a normal calling diagram, the iron sign cannot be disturbed unless something physically removes the token from the spot where it was placed (naturally, the called creature cannot disturb the token either directly or indirectly).
Demon Trap: As a full-round action, the demonbinder can set the token on a suitable surface and try to compel a free outsider within 30 feet of the token into its effective calling diagram (Will save negates, DC 10 + demonbinder level + demonbinder's Charisma modifier). The subject is entitled to spell resistance. If the creature fails its saving throw, it is transported to a square of its choice within 5 feet of the iron sign, and trapped just as if the demonbinder had conjured it into a calling diagram.
When a trapped creature leaves the iron sign (because it was freed by the demonbinder, escaped on its own, or the duration of the calling diagram lapsed), the token crumbles into powder and is destroyed.
Master Summoner Ex: At 3rd level, a demonbinder gains a +4 bonus on opposed Charisma checks to trap or compel creatures called through any planar binding spell.
Brazen Sign: On reaching 4th level, a demonbinder learns how to fashion a brazen sign. This works exactly like the iron sign, except that the called creature cannot use its spell resistance to attempt to break out of the calling diagram or to resist being caught in the demon trap. Crafting a brazen sign requires five days and the expenditure of materials worth 2,000 gp.
Infernal Certitude Ex: Due to his long study of demons, devils, and such creatures, a 5th-level demonbinder gains a +4 bonus on spell penetration checks against any outsider.
Silver Sign: On reaching 6th level, a demonbinder learns how to fashion a silver sign. This works just like the brazen sign, except that the DC of the Charisma check for the called creature to escape increases by +5, and none of its attacks or abilities can exit the area within 5 feet of the token. Crafting a silver sign requires seven days and the expenditure of 5,000 gp in materials.
Baleful Energy Ex: On attaining 7th level, when a demonbinder casts a spell that deals damage, one-half of the damage dealt is derived directly from infernal power and is therefore not reduced by resistance to the energy type of the damaging spell. In the case of flame strike, the entire damage of the spell is derived from infernal power and is not subject to fire resistance (although targets are still permitted spell resistance and saving throws).